Phylogeny, evolution and classification of Cuculiformes based on osteology, plumage ecology and behavior

The cuckoos are cosmopolitan, except in Antarctica and Arabic regions (North Africa and West Asia). It is an ancient lineage of Neoaves, with ancestral roots in Gondwana and about 70 mya estimated from both molecular analyses and oldest fossil record of Paleocene in Brazil. We performed a phylogenetic analysis based on parsimony of 402 characters from skeleton (n=230), plumage (n=152) and ecological/behavioral (n=20) data obtained from the examination of all currently recognized species (n=132). This analysis resulted in 89 equally parsimonious trees (1.339 minimum steps). The Bootstrap and Bremer indices indicated most nodes to be robust at all hierarchical levels and the majority of species was validated. Two main groups were observed: 1) Subordem Couides (Couidae: Coua/ Carpococcyx and Centropodidae: Centropus) with 13 synapomorphies and; 2) Subordem Cuculides (Neomorphidae (Crotophagidae (Taperidae (Phaenicophaeidae (Saurotheridae (Cuculidae)))))) with 11 synapomorphies. The terrestrial behavior (ground-feeders and ground-nesters) is basal (Couides), the both terrestrial/arboreal (ground-feeders and tree-nesters) is intermediary (Neomorphidae/ Crotophagidae/ Taperidae) and the arboreal (tree-feeders and tree-nesters) is derived (Phaenicophaeidae/ Saurotheridae/ Cuculidae). The brood parasitism evolved twice independently (Taperidae and Cuculidae), corroborating the molecular analysis. Finally, we offer here a classification for Cuculiformes based on this systematic analysis and contrasting with molecular analysis. Crotophagidae, Saurotheridae and Rhinortha were considered incertae sedis because they are in conflict between molecular data and this analysis.